Malicious PDF — malware analysis report

Static analysis result for SHA-256 66c59fbb4f3bd43b…

MALICIOUS

PDF

78.3 KB Created: 2021-09-16 17:53:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ba7b5871075da326bd3b74fa095d370b SHA-1: eb91239e455485496d6ff9d468353d8361e10cd2 SHA-256: 66c59fbb4f3bd43b231fd39ca88a8461e41c842cb17c2dfa8297c43bab9c1ce1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many hosted on compromised WordPress sites, suggesting an attempt to redirect users to malicious content. The heuristic firings indicate this PDF is part of a link farm designed to obscure malicious destinations, and ClamAV explicitly detected it as a phishing trojan. The embedded JavaScript likely facilitates the redirection or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://laborke.ru/uplcv?utm_term=mail+to+hr+sending+resume PDF link annotation
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/46b53c753196b5062cf692bab07a9393/44569991732.pdfIn PDF document text
    • http://kingsap.com/file_media/file_image/file/joxenatagotetikanoweduxad.pdfIn PDF document text
    • http://apismorava.eu/docs/38042752727.pdfIn PDF document text
    • http://antansconstructions.com/ckfinder/userfiles/files/31899504136.pdfIn PDF document text
    • http://gerocuki.hu/user/file/fusuku.pdfIn PDF document text
    • http://staceyasp.com/UserFiles/file/budomuzidupi.pdfIn PDF document text
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/5106cb9a24cd6485c40d5ba418b5983f/49689288419.pdfIn PDF document text
    • http://vin-baietii.ro/ckfinder/userfiles/files/62116274557.pdfIn PDF document text
    • http://metrocars.london/survey/userfiles/files/74447181947.pdfIn PDF document text
    • http://hnspkjx.com/d/files/samig.pdfIn PDF document text
    • http://startmatbaa.com/userfiles/file/boxog.pdfIn PDF document text
    • http://basketaci.cz/UserFiles/File/lakonamuvigavifumovasoje.pdfIn PDF document text
    • http://paintmaster.hu/js/ckfinder/userfiles/files/13404840492.pdfIn PDF document text
    • https://careersourceokaloosawalton.com/files/public/24140592004.pdfIn PDF document text
    • http://fcraregistration.com/UploadedData/file/xipemepinali.pdfIn PDF document text
    • http://tractortools.cz/ckfinder/userfiles/files/xeketalupojexawat.pdfIn PDF document text
    • https://razredna-nastava.net/files/vizuvewosobetuneroxofaj.pdfIn PDF document text
    • http://kxqcgs.com/filespath/files/20210903145008.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613b2ba2d31bf---tonanegiz.pdfIn PDF document text
    • http://imhyuk.com/imhyukeditor/userfile/file/suxidorata.pdfIn PDF document text
    • https://sevenhillsgroup.net/ckfinder/userfiles/files/64604110041.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cf37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF37 17128 bytes
SHA-256: 80dc6a1b84c05b39fe59812493ab3bd7178c5f40ebf305dcfcc7dc5d868c4804
font_01_sfnt_off0000fb36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001134d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1134D 10788 bytes
SHA-256: 7fa555449329abe04adbe4a4e15aea0f1e9042ee181158267e87944b850c27d3